Data cables typically include a core of twisted wire pairs with each individual wire being insulated. When foam insulation is used, crushing often occurs when the wire pairs are twinned or twisted together, which can result in unwanted reduction in conductor-to-conductor spacing. That is because foam is physically weaker in tensile and compressive strength than solid insulation. Also, in current foaming methods, it is often difficult to control foam percentages within the extrusion operation due to a multitude of factors, such as back pressure, melt strength, and catalyst integration. In addition, during normal extrusion processes, such as pressure extrusion, it is not possible to create certain shapes on the insulated conductor. That is because pressure extrusion makes adding channels and shapes very difficult around wires. Solid insulation, however, is typically more expensive and often fails flame testing because it generates much more smoke than foamed materials.
Therefore, a need exists for wire pair insulation that avoids crushing, that is less expensive, and that passes flame testing.